Containers for liquids and other flowable products in the form of light weight and highly flexible stand-up pouches provide the benefits of rigid packages, such as bottles and paperboard cartons, by providing the user with the capability of putting the pouch down between servings, as in beverage use; the marketer benefits from a classic billboard style of principal display panel when the container is shelved for merchandising at the retail level.
Flexible pouches that are mass produced from webs and sheets of flexible polymeric material with various forms of dispensing tubes are known in the art, and include dispensing pouches for flowable fluids described in U.S. Pat. Nos. 8,381,941 and 8,430,266, the disclosures of which are incorporated in their entirety by reference. Several embodiments of a beverage dispensing pouch that is thermoformed using sheets or webs of flexible polymeric material and having an integral straw for withdrawing the liquid contents by the user are disclosed in U.S. Pat. No. 9,187,225, the disclosure of which is incorporated herein in its entirety by reference.
Conventional stand-up pouches are generally made by forming a gusset in the bottom in order to provide a flat bottom surface, or base, for the upper portion of the pouch. The gussets formed on lightweight flexible stand-up pouch containers of the prior art are conventionally formed in one of two ways:
1. folding and sealing the edges of the flexible packaging material to integrally form the gusset from the same web or sheet of packaging material without cutting to produce a gusseted bottom with the front and rear panels extending upwardly to form the stand-up pouch;
2. adding a separate piece of folded material to the two sheets that become the front and rear panels that are then sealed along the periphery to form the gusset. Using the added separate piece allows the package to be constructed with a heavier gauge and somewhat more rigid, but still flexible material for the gusset producing the benefit of (a) a better package and/or (b) a more economical package because the thicker added piece allows thinner, less expensive material to be used for the much larger front and back panels.
In one embodiment of the '225 patent, the dispensing package with an integral straw is formed with a gusset in the base opposite the side from which the dispensing tube, or straw extends that allows the package to be positioned in an upright position on a horizontal surface. Shown in FIG. 1 is typical gusseted package 100 of the prior art which includes a container portion 110 formed by opposing sidewalls 112, base wall 114, top wall 116 that includes a dispensing tube 140 having a dispensing channel 142 closed by end seal 146 that is removable along tear line 144. The top cover sheet is heat sealed around the periphery 120 after the package is filled following thermoforming of the bottom sheet. A gusseted front panel 130 is illustrated with the gusset partially opened at 132.
Although the gusseted package configuration satisfies the desire to maintain the package in an upright position so that once the end of the dispensing straw has been removed for use, there is little risk that the liquid contents will be inadvertently passed from the end of the straw, it would be desirable to provide a package configuration and a method of its manufacture that could achieve the same or a comparable advantage without the need of forming a gusset.
Thus, the problem addressed by the present invention is how to simplify the manufacturing steps and the configuration of the finished highly flexible stand-up beverage dispensing package produced from relatively light weight thin gauge polymer films that can be thermoformed and heat sealed reliably for mass production of the product. Additionally, the desired package configuration, optionally configured with an integral straw, should minimize the risk that the liquid or flowable contents will escape from the open end of the package, or optional straw, when the package is placed on a horizontal surface during use.